/Engine/Source/Runtime/Engine/Classes/Animation/AnimInstance.h
Stops the animation montage. If reference is NULL, it will stop ALL active montages. Stopped montages will blend out using their montage asset's BlendOut, with InBlendOutTime as the BlendTime
void Montage_Stop ( float InBlendOutTime, const [UAnimMontage](API\Runtime\Engine\Animation\UAnimMontage) * Montage )